Bleached mahogany sulfonic compounds



BLEACHED MAHOGANY SULFONIC COMPOUNDS Manuel Blumer, Petrolia, Pa., and Gershon M. Goldberg, Waverley, Mass., assignors to L. Sonneborn Sons, Inc., a corporation of Delaware No Drawing. Application October 20, 1954 Serial No. 463,588

6 Claims. (Cl. 260-504) This invention relates to new and useful improvements in bleached mahogany sulfonic compounds.

In the hitherto practiced conventional bleaching of mahogany sulfonic compounds, such as petroleum mahogany sulfonates or their acids, bleaching agents of either an oxidative or of a reductive nature are used. Though some of these agents are capable of yielding bleached mahogany sulfonate products which possess desirably light color values (less than 10R Lovibond /2 cell), this desideratum is not always procurable with all mahogany sulfonate stocks. Furthermore, under the rigid conditions of heat stability test hereinafter set forth (heating for 5 days at about 220 F.), the bleached mahogany sulfonate products obtained in accordance with prior bleaching practices are not sufficiently light and heat stable and tend to darken upon storage. Finally, none of the hitherto known bleaching processes has been capable of obtaining substantial freedom from bloom (fluorescence, particularly of blue and purple hues). These defects inherent in the petroleum mahogany sulfonate products obtained in accordance with previously known bleaching practices, have militated against their wide use for a variety of purposes and especially in textile operations, such as for additives to textile preparations, including sizes, lubricants, softening agents, etc.

One object of the invention is the obtaining of a mahogany sulfonic product of substantial heat-and-lightstability; another object is such a product substantially free from bloom.

The foregoing and further objects of the invention will be apparent from the following description:

In accordance with the invention an organic solvent, and preferably a petroleum hydrocarbon solution of a mahogany sulfonic compound, is heated at a temperature of at least about 125 F. and below the decomposition temperature of said sulfonic compound, in the presence of a peroxidized mineral white oil.

The mahogany sulfonic compounds to which the inven tion is applicable comprise both the free mahogany sul fonic acid or acids as Well as the substantially oil-soluble salts or similar derivatives thereof. Their range of mean molecular weight as sodium salt is about 350 to 550, and they include both the petroleum mahogany sulfonic products conventionally obtained in the sulfuric acid or fuming sulfuric acid refining of petroleum oil distillates. and the synthetically produced, substantially oil-soluble, sulfonic materials of generally similar properties, such as the substantially oil-soluble alkyl aromatic sulfonic compounds.

Suitable organic solvents for the mahogany sulfonic compounds in accordance with the invention are those in which the latter are substantially readily soluble and which furthermore are substantially inert to peroxide oxidation. Particularly suitable solvents are, for instance, hydrocarbons or mixtures of hydrocarbons of the type and within the range usually present in the petroleum mahogany sulfonic acid or sulfonate containing oil layer derived from the sulfuric acid refining of petroleum oil iiui tumult-.1;

2,851,483 Patented Sept. 9, 1958 distillates. Such petroleum hydrocarbon oil solutions of petroleum mahogany sulfonic acids or sulfonates may thus furnish a convenient source of the raw material for the organic solvent solution of mahogany sulfonic compounds to be treated in accordance with the invention. Useable hydrocarbons are thus preferably those covering a viscosity range between about 50 and 400 seconds Saybolt at F.

The peroxidized hydrocarbons useful in accordance with the invention are preferably one or a mixture of such hydrocarbons within the range of petroleum oil neutrals of a viscosity range (non-peroxidized) of substantially 30-400 seconds Saybolt at 100 F. Best results are obtained with a petroleum mineral white oil type composition with viscosities (non-peroxidized) of about 50-150 seconds Saybolt at 100 F. The hydrocarbon, such as petroleum mineral white oil to be peroxidized, may be substantially pure in the sense of being substantially finished to the point of freedom from sulfonatables, or may be a product of technical purity in the sense of containing up to about 5% sulfonatables. Within the preferred scope of the invention the sulfonic compound solvent as well as the hydrocarbon to be peroxidized, are constituted of hydrocarbons Within the petroleum neutrals range and having viscosities of 30400 seconds Saybolt at 100 F.

Pei-oxidation of the hydrocarbons for the purpose of obtaining the peroxidized hydrocarbon material useful in accordance with the invention is best obtained by blowing air or other oxygen-containing gas through the hydrocarbon by means of a suitable gas-dispersion device, such as a gas bubbler, while maintaining the temperature of the material substantially at about 200 to 265 F. It is advisable that the gas, such as air, be as dry as possible as any appreciable moisture content thereof may give rise to the undesirable formation of acids. Usually a considerable induction period is observed and may be as long as 48 hours. Once peroxide formation has started, i. e., at the end of the induction period, the same pro ceeds relatively rapidly and is usually completed in an additional 5 to 10 hours.

The normally obtainable optimum yield of peroxide formation is somewhere between 0.6 and 12% by weight of the oil, calculated as H 0 This yield, however, may be increased up to about 15% or more, by the presence in the hydrocarbons of small amounts of free alkali. Thus 0.02 to 0.05% and preferably 0.33% of free alkali, calculated as NaOH, by way of weight of the hydrocarbon present, give good results. The induction period can be reduced by conducting the oxidative blowing in the presence of relatively small amounts of previously peroxidized hydrocarbon. In that case good results are obtained by a peroxide content of at least 0.0750.1% by weight of the hydrocarbon, calculated as H 0 equivalent. The course of the peroxidation reaction can be followed in each case by titration of samples taken at regular intervals in the usual manner.

Depending on conditions, the above mentioned induction period is at least to some extent a function of temperature, so that appreciably shortened induction periods are obtainable near the upper limits of the peroxidation temperature range above set forth even without the addition or presence of free alkali or previously formed peroxides. Though certain type catalysts, such as iron, cobalt, nickel, etc. may be also used to expedite the peroxidation reaction, these cannot always be recommended since they may also lead to undesirably large formation of acids, aldehydes, etc.

Within the scope of this invention the peroxide should be present in amount of at least 0.01% and preferably 0.010.025% by weight, calculated on H 0 per total solvent, such as hydrocarbons, plus sulfonate present lustration:

and at least to the extent of 0.020.08% and preferably 0.05-0.08% by weight of sulfonic material. Top amounts of peroxide are solely limited by the capacity for peroxide formation of the particular hydrocarbon without appreciable decomposition producing acids or aldehydes. Thls capacity is normally limited to a top of 1.01.5% of peroxide by weight of the peroxidized hydrocarbon, calculated as H In all cases the amount of peroxidized hydrocarbon and the heating time are so adiusted that the resulting products show a definite peroxide reaction evidencing the continuing presence of peroxides therein. Heating times depend upon temperature used as well as upon the presence or absence of accelerators, such as C -C aliphatic alcohols. The bleaching reaction is considered complete when upon further heating for 24 hours no appreciable additional color reduction is ascertainable.

The temperature at which heating with the peroxidized hydrocarbon is carried out in accordance with the invention is not critical except as a function of time, there being however a minimum temperature requirement of about 125 F. and -a maximum coincident with the decomposition of the sulfonic compounds.

Within the preferred embodiment of the invention the treatment of the mahogany sulfonic products with peroxidized hydrocarbons is carried out in the presence of 5l5% and preferably 8-12% by volume of an aliphatic C -C alcohol, such as methyl. ethyl, propyl or isopropyl alcohol, based on the total sulfonic compound-hydrocarbon solution present. Improved bleaching results and/or accelerated bleaching times at lower temperatures are thereby obtainable.

The novel products obtained in the practice of the hereinabove referred to method in accordance with the invention are substantially stable against discoloration or exposure to heat or light and are substantially free from bloom.

By Way of further embodiment of the invention, novel, substantially heat-and-lightstable products may be obtained not only by the bleaching reaction above set forth. but also by the addition of a peroxidized hydrocarbon of the type herein mentioned to a mahogany sulfonic compound bleached by some other method.

Where reference herein is made to substantial heat stability or such similar expression is used in connection with mahogany sulfonic compounds, and especially petroleum mahogany sulfonic compounds, there is in tended to designate thereby a heat stability of an Organic solvent solution and particularly hydrocarbon of the petroleum neutrals type) solution of such mahogany compound, to the extent of withstanding heating for five days at a temperature of about 220 F. with a Lovibond R color increase (16" cell) of less than 50% and preferably less than 20%.

As a practical measure of desired results to be achieved in accordance with the invention, substantial freedom from bloom is the primary criterion to be achieved. By way of color reduction, it is. as a practical matter, desirable in most cases to continue the heating with the peroxidized hydrocarbon for a suflicient length of time to obtain a Lovibond /2" cell) color reduction of at least 10 and preferably in the R values thereof.

The following examples are furnished by way of il- EXAMPLE 1 1250 parts by volume of a filtered 100 viscosity (Saybolt at 100 F.) white oil (from a Mid-Continent distillate) are heated in an iron vessel to about 255 R, whereupon air was blown through the oil by means of a sintered glass bubbler. The oil temperature is kept between 255 and 265 F. and air blowing is continued for 12 hours. The course of the reaction is followed by titration in the conventional manner, using an iodometric method, using isopropyl alcohol as diluent, adding measured amounts of potassium iodide and glacial acetic acid, and titrating with 0.1 N aqueous sodium thin sulfate solution. At the end of approximately 12 hours air blowing, the hydrocarbon solution is equivalent in peroxide concentration to a 1% by weight hydrogen peroxide solution (calculated as H202).

A petroleum mahogany sulfonate solution containing 65% by weight of sodium sulfonate (mean molecular weight about 425) and 35% by weight of retained oil is then admixed with 30% by weight of the peroxidized mineral white oil to yield a 50% by Weight of petroleum mahogany sulfonate solution having an undiluted Lovibond color of about 10R /2" cell) and a bloom involving a blue to purplish fluorescence.

When heating the mixture for about 10 hours the color is reduced to 67R /2" cell) and the bloom has substantially disappeared. When subjecting the resultant product to heating at 260 F. for a period of 5 days, a color reversion to only 7-8R without reappearance of bloom is observed.

EXAMPLE 2 Portions of the same 6535 petroleum mahogany sulfonate solution specified in Example 1, but diluted on a 5050 volume basis with isopropyl alcohol, was admixed with the same amount by volume of peroxidized mineral white oil obtained as specified in Example 1, using however for each different portion a peroxidized oil of different peroxide concentration, defining H 0 equivalents, as of 0.2%, 0.4%, 0.6% and 0.8% by weight respectively; the results obtained in each case after 6 hours heating at about 225 F. are shown in the following table:

Table Color. Percent H2O: cqu. Lovibond, Bloom lcell 8R some bloom. 7l-R no bloom. .SBQR Do. 5R D0.

EXAMPLE 3 r A petroleum mahogany sulfonate solution as specified in Example 1 but containing about 12 parts by volume of isopropyl alcohol and about 35 parts by weight of EXAMPLE 4 Example 3 is repeated except that an amount of peroxidized white oil is used which yields, upon removal of alcohol, a total of 60% by weight sulfonate solution; after the substantial removal of the alcohol, the resultant product shows a Lovibond color /2 cell) decrease from the original 12.5R to 7.5R and elimination of the original purplish-blue bloom.

EXAMPLE 5 Example 4 is repeated except that the sulfonate is one having a mean molecular weight of 375; the resultant product shows a Lovibond color decrease from the original 20R to 15R and elimination of the original purplish blue bloom.

The method in accordance with the invention is conveniently practiced as part of the refining preparation of petroleum mahogany sulfonic compounds. At various stages of such operations heating must be effected and diluent hydrocarbon oil is added. Such a stage is, for instance, represented by the dehydration and/or alcohol solvent removal step conventionally practiced in the manufacture of petroleum mahogany sulfonic materials.

Diluent oil could then be added in the form of a peroxidized oil at such a stage to thereby simultaneously effeet the bleaching. This is, for instance, illustrated in the following example:

EXAMPLE 6 8% by weight of a peroxidized mineral white oil specified in Example 1 was added to an alcoholic solution of petroleum mahogany sulfonate containing about 10% occluded oil, 14% Water, 20% sulfonate and 56% isopropyl alcohol. After heating the mix to thereby distill off the alcohol and effect dehydration of the mix, the resultant product shows a Lovibond color /z" cell) decrease from an original 13R to SR and elimination of the original purplish-blue bloom.

When substituting the foregoing examples for neutrals and specifically those within the individual viscosity ranges of 50-100, 100-150, 150-250, and 250-350, or using other mahogany sulfonic compounds within the mean molecular weight range hereinabove mentioned, or using ethyl or propyl alcohol, substantially similar results in color reduction and elimination of bloom are obtained as specified in these examples.

Wherever Lovibond color is specified herein, the same is intended to designate undiluted solution.

We claim:

1. In the production of substantially oil-soluble mahogany sulfonic compounds of light color and free from bloom or fluorescence, the improvement which comprises heating an organic solvent solution of such compound at a temperature of at least about 125 F. and below the decomposition temperature of said compound, in the presence of a peroxidized hydrocarbon solvent therefor,

saidhydrocarbon in non-peroxidized form being a petroleum mineral white oil type and having a viscosity range of from about 30-400 seconds Saybolt at 100 F. and not over about of sulfonatables in amount and of a peroxidized concentration suflicient to yield for the total sulfonic compound and oil present, a peroxide concentration of at least 0.01-0.025% by weight calculated as H 0 and for said compound at least equivalent to 0.02-0.08% by weight calculated as H 0 said organic solvent being substantially inert to reaction with said peroxidized hydrocarbon solvent.

2. Improvement according to claim 1 in which said peroxidized oil is in amount and peroxide concentration at least equivalent to ODS-0.08% by weight calculated H 0 per weight of sulfonic compound.

3. Improvement according to claim 1 in which said mahogany sulfonic compound is an alkali petroleum mahogany sulfonate.

4. In the production of substantially oil-soluble mahogany sulfonic compounds of light color and free from bloom or fluorescence, the improvement which comprises heating an organic solvent solution of such compound at a temperature of at least about 125 F. and below the decomposition temperature of said compound, in the presence of a peroxidized hydrocarbon solvent therefor, in the presence of 5-15% by weight of an aliphatic C -C alcohol per volume of total sulfonate and organic materiat, including peroxidized hydrocarbon solvent present, said hydrocarbon solvent in non-peroxidized form being a petroleum mineral White oil type and having a viscosity range of from about 30-400 seconds Saybolt at F. and not over about 5% of sulfonatables in amount and of a peroxidized concentration sufficient to yield for the total sultonic compound and oil present, a peroxide concentratiin of at least 0.0l-0.025% by weight calculated as H 0 and for said compound at least equivalent to 0.02-0.08% by Weight calculated as H 0 said organic solvent being substantially inert to reaction with said peroxidized hydrocarbon solvent.

5. Improvement according to claim 4 in which said peroxidized oil is in amount and peroxide concentration at least equivalent to ODS-0.08% by weight calculated H 0 per weight of sulfonic compound.

6. Improvement according to claim 4 in which said mahogany sulfonic compound is an alkali petroleum mahogany sulfonate.

References Cited in the file of this patent UNITED STATES PATENTS 1,734,050 Seck Nov. 5, 1929 2,201,119 Blumer et al. May 14, 1940 2,447,794 Brewer Aug. 24, 1948 2,454,826 Liberthson Nov. 30, 1948 2,486,373 Blumer Nov. 1, 1949 2,605,290 Robertson et al. July 29, 1952 

1. IN THE PRODUCTION OF SUBSTANTIALLY OIL-SOLUBLE MAHOGANY SULFONIC COMPOUNDS OF LIGHT COLOR AND FREE FROM BLOOM OR FLUORESCENCE, THE IMPROVEMENT WHICH COMPRISES HEATING AN ORGANIC SOLVENT SOLUTION OF SUCH COMPOUND AT A TEMPERATURE OF AT LEAST ABOUT 125*F. AND BELOW THE DECOMPOSITION TEMPERATURE OF ABOUT COMPOUND, IN THE PRESENCE OF A PEROXIDE HYDROCARBON SOLVENT THEREFOR, SAID HYDROCARBON IN NON-PERIOXIDIZED FORM BEING A PETROLEUM MINERAL WHITE OIL TYPE AND HAVING A VISCOSITY RANGE OF FROM ABOUT 30-400 SECOND SAYBOLT AT 100*F. AND NOT OVER ABOUT 5% OF SULFONATABLES IN AMOUNT AND OF A PEROXIDIZED CONCENTRATION SUFFICIENT TO YIELD FOR THE TOTAL SULFONIC COMPOUND AND OIL PRESENT, A PEROXIDE CONCENTRATION OF AT LEAST 0.01-0.025% BY WEIGHT CALCULATED AS H2O2 AND FOR SAID COMPOUND AT LEAST EQUIVALENT TO 0.02-0.08% BY WEIGHT CALCULATED AS H2O2, SAID ORGANIC SOLVENT BEING SUBSTANTIALLY INERT TO REACTION WITH SAID PEROXIDIZED HYDROCARBON SOLVENT. 